/*
 * Copyright 2011 J. Auer, J. Andert, F.-J. Jendrusch, U. Celebi
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package de.fuberlin.replication.storage;

import de.fuberlin.replication.library.Metadata;
import de.fuberlin.replication.library.Subset;

/**
 * Data Access Object (DAO) interface for metadata in the replication metadata storage.
 * 
 * @see Metadata
 */
public interface MetadataDAO {
	/**
	 * Returns all metadata.
	 * 
	 * @return all metadata.
	 */
	Iterable<Metadata> getAll();

	/**
	 * Returns all metadata in the given subset.
	 * 
	 * @param subset the restricting subset.
	 * @return all metadata in the given subset.
	 */
	Iterable<Metadata> getAll(Subset subset);

	/**
	 * Returns the metadata matching the given name.
	 * 
	 * @param name the restricting name.
	 * @return the matching metadata, null if no metadata matches.
	 */
	Metadata get(String name);

	/**
	 * Persistently stores the given metadata as element of the given subset.
	 * 
	 * @param subset the metadata enclosing subset.
	 * @param metadata the metadata to be stored.
	 */
	void save(Subset subset, Metadata metadata);

	/**
	 * Deletes the given metadata.
	 * 
	 * @param metadata the metadata to be deleted.
	 */
	void delete(Metadata metadata);

	/**
	 * Returns the latest time stamp of all metadata.
	 * 
	 * @return latest time stamp of all metadata.
	 */
	long getLatestTimestamp();
}